Automatic air-brake.



No. 70l,98l. 'Patented lune l0, I902.

v G. T. WOODS.

AUTOMATIC AIR BRAKE.

(Application filed Feb. 5, 1901. (No Model.) 3 Sheats-Sheet l.

WEI/265505: Irma/ eta! llfl a. 114M m: NuRms PETER! 00.. FNQYO'LITHO"wnsumowu. u. c.

AUTOMATIC MBv B RA'K'E- (Application filed Feb. 5, 190 1J (No Model.) 3Shae'ts-Sheet 2.

Train 7 BRAKE CYLINDER I [29' AUXILIARY mzsgRvom MAIN RESERVOIR- THEnoRms VETERS o0. PNOTO-UTHO.. WASHINGTON. n c.

7 N0. 701,,Q8l.

G. T. WOODS.

AUTOMATHI AIR BRAKE. Application filed Feb; 5, 1901.1

Patentd lune IO, 'l902.

3 Sheets-:Sheat 3k (No'ModeL) W a I.) m n H W g M A M Q m INVENTOR-WITNESSES: WW6:

THE nonms PETERS co PNo'rcsuTNO WASHINGYON, n. c.

UNITED STATES;

PATENT GRANVILLE T. WOODS, OF NEW YORK, N. Y., ASSIGNOR, BY MES NEASSIGN- MENTS, TO THE WESTINGHOUSE AIR BRAKE COMPANY, OF PITTSBURG,PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

A UTOMATIC AlR-BRAKE.

SPECIFICATION formingpart of Letters Patent No. 701 ,981, dated June10,1902.

Application filed February 5. 1901. Serial No. 46,0 80. (N model.) a

To all whom it may concern:

Be it known that I, GRANVILLE T. Woonsp a citizen of the United States,and 'a-resident of New York, in the county of New York" and State of NewYork, have invented certain new and useful Improvements in AutomaticAir-Brakes, of which the following is'a specification. V I

My present invention relates to the pecul- 1o iar construction andarrangement of: the valves and other parts of an automatic brakemechanism which is preferably operated by compressed air. My inventionhas for one of its objects to I5 compel a positive action of each brakewhen the same is expected togoon, to stop the car, or to come off, andthereby release the car.

Railway accidents are reported frequently :0 as being due to the failureof the air=brake systems; and it is one of the objects of my presentinvention to avoid some of the weak points of the familiar systems indaily use. The brake system in general to which my 2 5 presentimprovements are shown applied is that in common use and includes; iiiaddition to the brake-cylinder, auxiliary reservoir, and train-pipe, theusual equipment on the locomotive-such as an air pump or compressor, 3oastorage-tank, and an engineers va'lve-all.

of which parts are familiar to persons skilled in the construction andoperation of brake mechanisms. In addition to the parts named a completeautomatic air-brake system .in-

5 eludes as one of its essential elements a valve mechanism located oneach car and'servin g to control the ad mission and escape of air in thebrake-cylinder for elfectin g the application .and release of thebrakes. Such valve mech- 0 anism is popnla'rly known as triple-valve Imechanism, and the present improvements relate more particularly to thevalve element or part of the brake system and introduces a peculiar modeof operation, notwithstanding V the fact that I employ the usualpressure of air when causing a gradual application of the brakes andalso when a quick-action or emergency stop is being made, the gradualapplication being produced by energyfrom the auxiliary reservoir; butthe quick and thus add greatly to the reliability of the commonair-brake-equipment.

action is'caused by an initial air-supply from the train-pipe to thebrake-cylinder and a final y air-supply from said auxiliary reservoir tothe said brake-cylinder.

l ljtris well known to those skilled intheprofession oflocomotive-running that-if an airlbrake on'on e' 'car fails to go on itnot only causes the loss'of the braking effect'of that particularcar-brake, 'butit'also causes the other brakes of the train to lag orgofon'slo wly, 6o

b'ecausethe air pres'sure i'n the trairi-pipe-in such cases is notreduced quickly,-;therefbeing one less brake-cylinder to take a portionof said air from said train-pipe andxither'eby accelerate theremaining-valve apparatus; :It is also well known thatif anem'ergencystop is made at a time when the brakesystem is normal the time anddistance required in which to make the stop is short, w11'ile the sametrain will require a'lohger time anddi's- 7o tan'ce in'which to ceaseits motion'when the brakesystem is 's'ligh-tlyabuormal. The dif-'ference between the'short timeand distance demanded in 'the one'case andthe longer time and distance required inthe other case iisi often thespan between life and death.

To insure afar more positiveypowerf-ul, and

aim uch quicker'actionthan ispossibleto be ob I tained by the use of thefamiliar systems aforesaid, lh'ave provided a'novel construction and Soarrangement of the main'or double-acting valve part; the valve of whichmay be of any suitable kind and combined'with the valve piston part (1term the combination a f 'valve device) and the various ports, sothatnot; only will the valves and other parts cooperate, butthey may beincorporated with the valve mechanism of the well kk'nownfwestinghouseair-brake system or any formi'of'air-brake which will operateinterchangeably with'said Westinghouse system. Furthermoraby theaddition of one of my valve devices? toF-each car which is at present"supplied with the said Westinghouse system or the New 'York air-brakeapparatus or some similar equip- 5 ment at system will thereby beproduced which will embody the majority of the most valuable features ofmy present invention,

To more fully understand my invention, reference is made to theaccompanying drawings, in which-- Figure 1 is a side view of the outsidecase of my invention. Fig. 2 illustrates a sectional view of the casingand some of the parts of Fig. 1. In Fig. 3 is shown a sectional view ofsome of the parts and a full side View of other parts of a modificationof my invention. Fig. 4 is a side View of the valve-piston part. Fig. 5is a face view looking from right to left of said valve-piston part.Fig. 6 is an enlarged sectional view of the valve device illustrated inFigs. 2 and 8. Fig. 7 illustrates one way of connecting up thebrake-system, so that it one of the valve devices or a valve should failto operate the other valve device will operate, so that thebrake-cylinder will be certain to receive the air-pressure required forits operation. Fig. 8 is a sectional view of the valve devices and theircasings when such are arranged as shown in Fig. 7.

In Fig. 1 the part indicated by numeral 1 is an air vent or box which isfilled with cotton or some other suitable porous material, so that whenthe air is drawn through the same from the outside atmosphere, ashereiuafter set forth, the porous material then acts as a filter,serving to prevent grit or dirt from entering the valve-chamber orvalvespace which is within the valve-case. Valves 2 and 3 are controlledby moving handle 4 upward or downward. The direction in which saidhandle is moved will of course depend upon which of the air-passages areto be opened and which are to be closed. Said handle connects withvalves 2 and 3 through rod or bar 5, as shown in the drawings. 6 6 areguides for bar 5. The ends of said bar and the outer ends of said valvesare provided with teeth, so as to produce What is termed arack-and-pinion movement. 7 and 8 are the passage-ways or air-pipescontrolled by valves 2 and In Figs. 2, 4, 5, 6, and S I have shown thevalve device which controls the various ports. When I use the wordsvalve device I mean the valve-piston and the main valve acting asdifferent parts of one device, one of said parts controlling theadmission of air from the auxiliary reservoir to the brake'cylinder,while the other part governs the air-admission from the train-pipe tothe brake-cylinder. The valve device or, in other words, the valve-likedevice and the parts connected thereto are more clearly illustrated inFig. 6, which is the preferred form, enlarged so that the parts may bemore readily indicated and understood, and the same may be used as areference to assist in the explanation of Fig.

2, the. The preferred construction of said apparatus is as follows: Themain-valve part, as shown in this case, is what is technically termed apiston-valve and the piston part to which said valve is connected and bywhich it is moved is (in the present art) technically termed avalve-piston, each part being so named because of its peculiarconstruction, movements, and the work it performs. The main-valvepartherein shown has three partitions E E E These are fixed upon stem13, which in turn is firmly attached to the hub 14: of the valve-pistonpart. The valve-piston part of the valve device may be made in onepiece, as shown in Fi 3, or it may be composed of several parts, asshown in Fig. 2. The valve-piston part has one or more ports or passages15, leading through the web or wall 16 into piston-port 17 in the bodyof the said piston, thence out at the port-opening between the wall 18and flange 19. In Figs. 2, 6, and S the said ports 15 are closed one wayby check-valve 20, which is held to its seat by spring 21. In practicethe space between flanges 19 and 22 is sufliciently great to normallycover port 23, which (when open or uncovered by the valve-piston part)leads from the train brakepipe through passage 11 to the brake-cylinder.The three partitions E E E of the mainvalve part are arranged in thefollowing manner: Partitions E and E are so arranged that the restrictedport 2 L is normally between them, while the restricted exhaust-port 25is always between them. Port 26 is always between partitions E and Ewhile port 27 is normally between partition E and wall 18. Now as thevalve device moves from the extreme end of its path at the left to theother extreme end of its path to the right (as in emergency stops) thenpartition E moves to another position between ports 21 and 25. PartitionE remains in its normal pathway between ports 25 and 26, while partitionE takes up a new position between port 27 and wall 18, at which time thebrakes will go on. \Vhen the engineer causes the valve device to move totake off the brakes, said partitions take up their normal positions tothe left. In Fig. 3 the check valve 20 is arranged in a valve-boxoutside of the case A. In this arrangement valve 20 normally covers port28. When valves 2 and 3 are open, as in Fig. 2, then passage 7 leadsfrom the anxiliary-reservoir opening 30, around through valve 2' toopening 11, thence to the brake cylinder.

In some brake systems the auxiliary reservoir is charged to the samerestricted port or passage which communicates between the auxiliaryreservoir J and the brake-cylinder I. In my apparatus as illustrated inFigs. 2, 3, &c., the passage 28 is for charging the auxiliary reservoirJ, and said passage is arranged as a by-pass-that is, it provides alarge direct passage around the restricted port (through which air issupplied from the auxiliary reservoir to the brake-cylinder) directly tothe opening 30, leading to the auxiliary reservoir, thus avoiding theslow reservoir-recharging process used in said familiar systems. By thearrangement herein set forth the engineer is permitted to recharge theauxiliary reservoir while the brakes are,

of the portsand valves, andits value is great when. along heavy train isrunning downgrade and' the engineer desires to keep the train undercontrol. It is well known that when the brakes are on .the airconstantlyleaks'frorn-the brake-cylinder. Hence the necessity of =-recharging theauxiliary reservoir while the brakes are on.

.It will be observed that valves 2 and 3 "(shown in Fig.3 and also inthe upper portjion X of Fig. 8) are set to obstruct the passages? and 8,which said'valves control, while in Fig. 2 and also the lower part Y ofFig. 8

Ilvalves 2 and 3f are set to permit an open way through said passages.

ffnever set to obstruct the air-passages except These valves are whentwo valve "devices and their inclosi'ng cases communicate with onebrake-cylinder,

as shown in Figs.= 7 and8, one of saidvalve devices acting as agraduating main'valve,

while the othervalve device acts as an emergency-valve only,operatingonly when emera gency stops are'bei-ngmade. Whenever two valve devices.;are coupled up, as shown in Figs. 7 and 8-, onejof the said devices isconverted into a differential piston-.-thatis to say, the valves'2 and3, while being turned, as shwnin said figures, so as to obstruct thepassages 7 and 8,1eading toor from the valve-piston part,willsimnltaneously open a passageleading from theouter end E of themain-valve part, through box or vent 1, to the outer atmosphere. Now ifairunder pressure is admitted to both sides of the valve.-

I piston part the total number of pounds use-.

ful pressure upon. the said piston surface next to partition IE will beless'thanthe total numberof pounds useful pressure on the'pis-.

ton-surface next to the adjusting-stem 31,

this difference inthe useful pressures be-.

ing due to the counteracting influence of the surface of partition'E",which'is so exposed as to oppose the pressure against thepistonsurfacenext thereto. as partition E is not exposed to theair-pressure when said air-passages are obstructed the end surfacethereof cannot be taken into' the calculation. The surfaces of partitionE and piston-wall 18 should be so proportioned that the arrangement as adifferential piston will remain quiescent unless required. to act whenmaking an emergency stop, at. 1 which time about twenty pounds reductionis 'made in the train-pipe air-pressure, so that the preponderance .ofpressure will be on theauxiliary-reservoir side of said piston part.

Then the auxiliary-reservoir air-pressure will move the saiddifferential piston backtoward the rightuntil it reaches the extreme.

limit' of its path, as hereinafter explained, thus acting absolutelyindependent of any motion (or the effect of'any motion) which theassociate graduating main-valve device may make. g

It will be noted that:

InFig. .7 I have shown a main air-pressure reservoir, an auxiliaryreservoir, a brake-cylinder, two valve devices X and Y, an engi- 7cdischarge-limit valve is to prevent the escape of more than apredetermined amount of air through the 'action of the engineers valvewhen an emergency stop is to be made. I It is I well understood thatwhen an emergency stop is to be, made the engineer suddenly dis.- Icharges twenty pounds (more or less) from thetrain-pipe. I When saidreduction of trainpipe pressure takes place, the valve mechan: ismshould act promptly, to admit air from the train-pipe and also from theauxiliary reservoir to. the brake-cylinder. Now when, an emergency stopis required the engineer has no time to gage the escaping air..Therefore a much greater reduction of the air-pressure takes place thansuch cases demand, thus re- 0' ducingthe amount of compressed airwhichshould have. passed from the trainrpipe into the brakecylinder insteadof being discharged into the atmosphere, and thereby reducing theefficiency of the brake system and 5 'adding to the time required toeifect a stop.

Thearrangement of the discharge-limit valve is as follows: Parts 35 and36 form the two heads of a difierential piston, said heads beingconnected by a stem, as. shown, or head Ico 35 may be made inthe form ofa plunger, if

so desired. This said piston moves within a case or cylinder in theusual way, as shown. The usual vent isindicated at 37; An, airereservoiris shown at H and a check-valve atv38. The operation-is as follows: Thelever 390f the engineers valve is shown in position .toadmit airunder'pressurefrom reservoir K'throu'gh i pipe 42 into the space betweenthe valve-heads I 40 and 41, thence throughpipe 43, under pisno ton-head36,then to the train-pipe. Meanwhile, some of the air forces its waypast checkwalve '38 and accumulates in reservoir H and the tubularcommunications immediatelyoonnectt ed therewith. Thus there will bea'pressure 11 5 against both ends ,or heads of. saiddifferenr. tial;piston, and when the pressure in-said reservoir H is equal to thatinxthe train-pipe: the check-valve'38 will be seated andthe air. inreservoir Hwill .be .entrappedor con- 12o fined. The under surface ofhead 36 being, greater in square inches than the upper sur-. face ofhead 35 permits the preponderance;

of pressure to movethe piston upward tothe. position shown in thedrawings. Now if the engineer pulls lever 39- to the right until itreaches the limit of its travel by being brought 5 up against screw. 45then air will rushout from the train-pipe and past the. outer end ofhead 41. As soon as the pressure in the train- 1 0 pipehas been reducedto the predetermined limit the preponderance of pressure will .then;

be against the small head 35of said differen-i tial piston,.andtherefore said pistonwill be forced down to its seat. In other words,the pressure of the said entrapped air is not reduced by the reductionof the train-pipe pressure. Therefore when the train-pipe pressureis'reduced to a point where its total nu mber of pounds pressure againsthead 36 is below the total number of pounds pressure exerted againsthead 35 by the entrapped air then the said piston will be forced down toits seat, and thereby limiting the reduction of the train-pipe pressureby closing or obstructing the train-pipe at the appropriate moment, thuspermitting the air to be trans ferred while at its highest permissiblepressure from the train-pipe to the brake-cylinder. When the train-pipeis to be recharged, lever 39 is moved to the position shown in thedrawings. Then air will pass from the reservoir K, as hereinbefore setforth, until it reaches passage 44, through which the air has access tothe under side of piston-head 36, which will then be forced upward untilit reaches the position shown in the drawings. Air will in the meantimerecharge the trainpipeand the auxiliary reservoirs. It will be notedthat the discharge of air is automatically limited or stoppedindependently of the engineers valve. When connecting up a single valvedevice to a car, connections are made between the train-pipe andvalve-case A, as follows: A branch pipe leads from said trainpipe andconnects with said case at point 10. Another connecting-pipe is placedbetween the brake-cylinder and said case at point 11, while a third pipeconnection is supplied between the auxiliary reservoir and said case atpoint 30. The train-pipe has the usual conneetions from car to car, &c.When a single valve device is used, the operation is as follows: Tocharge the auxiliary reservoir and prepare the brakes for action, air atabout seventy pounds pressure is permitted to flow from the mainreservoir K through the train-pipe and its connections into opening 10,(of valvecase A,) thence through chamber B, passages 50, ports 15,around check-valve 20, through piston-port 17 port 28, passage 30, tothe auxiliary reservoir. Aportion of the air passes along throughpassage 7, valve 2, to the outer side of partition E. In the meantimethe valve device has been forced to the extreme left of case A. Thus thebrake-cylinder is cut 01f from the train-pipe and the auxiliaryreservoir, and the exhaust-passage is open between the brake-cylinderand the atmosphere. When it is desired to apply the brake gradually, thehandle 39 of the engineers valve will be moved for a moment to such aposition that communication between the main reservoir K on the engineand the trainpipe will be closed and an escape-passage is open betweenthe train-pipe and the atmosphere. Thereby the air-pressure in thetrainpipe will be reduced about five pounds. This reduction of pressureon the train-pipe side of the valve-piston part disturbs the balancepreviously existing on the opposite sides thereof, resulting inestablishing a preponderance of air-pressure on the auxiliary-reservoirside, and the air delivered from the auxiliary reservoir through passage30 and acting upon the valve-piston part causes the valve device to movetoward the right. This movement will'continue until partition E haspassed to the right ofport 24, thus allowing auxiliaryreservoir air toflow through passages 30 and 7, valve 2, to port 24, thence throughpassage 8 and valve 3, passage 11, to brake-cylinder, where it actsuponthe piston thereof to cause the brakes to go on. When by reason ofthe flow of air intothe brake-cylinder the pressure in the valve-chamberahd auxiliary reservoir has been reduced to or below that of thetrain-pipe, a slight return or leftward movement of the valve devicewill be prod uced,(by the combined action of the trainpipe pressure andthe adjusting-stem 31), sufficient to cause the partition E to rest uponand close port 24, and thus close communication between thevalve-chamber and the brake-cylinder and confine the air admitted withinthe latter. In case it is desired to gradually increase the air-pressurein the brake cylinder the above operation is repeated. To permit the airin the brake-cylinder to escape and let elf or release the brakes, theair-pressure in the train-pipe is restored or increased by a proper andwell known movement of the engineers valve. The increase of pressure inthe train-pipe causes the valve device to move leftward to the limit ofits path, when it will occupy the position shown in Fig. 2, 850.,thereby placing restricted port 24 in communication with exhaust-port 25and allowing the brake-cylinder air to escape. It should be understoodthat in practice I cause the passage which directly connects withexhaust-port 25 to be much more restricted than any of the other saidpassages, thereby causing the exhaust from the brake-cylinder to be verygradual. At the same time the restoration of the pressure in thetrain-pipe will unseat check-valve 20, (after the piston-port 17registers with port 28,) and air from the train-pipe will flow into theauxiliary reservoir, recharging it for future use. The pressure in theauxiliary reservoir will then equal that in the train-pipe, when thecheck-valve 20 will be seated by its spring 21. When it becomesnecessary to recharge the auxiliary reservoir while the brakes are on,the engineer moves his valve suddenly and connects the main reservoir Kto the train-pipe. This causes the valve devices to move quickly to thefull limit of their paths toward the left, thus placing the auxiliaryreservoir in communication (through large passages) with thefully-charged train-pipe, thus causing the auxiliary reservoir to becharged in an instant. The passage from the brake cylinder through theexhaust (said passage being open while said recharging was beingaccomplished) is quite small or restricted at the ports. Therefore theair which is confined in said brake-cylinder will have escaped butslightly before said auxiliary reservoir was fully chargedland theengineer dischargedsome airv from the train-pipe as when firstapplyingthe brakes; Thus-it will be. noted that the brake-cylinder waspermitted to receivea second supplyof air-pressure before the firsts'upplywas exhausted.

' When itbecomes necessary ordesirable to apply the brakesquickly andwith full power for an emergencyzstop, the e'ngineers valve Willbe movedto close .the communication between the main reservoir Ktandthetrainpipe and open the latter .to the atmosphere andiproduce a suddenreduction of pressure of about twenty pounds in the train-pipe. Theeffect of this sudden diminution of pressure in the train-pipe vis.immediatelywmanitest at the v-discharge limit ,valve (which actsinstantly) and the nearest valve device or that on the firstcanciausinglthe valve device to be movedbythehigher pressure ofauxiliary-reservoir airquic'kly toward the right to the endof its path..Then port 23'r egisters with the piston-port'ilfof the valve-pistonpart, and thereby placingthe auxiliary res'er Voirand the train-pipeinlcommunication with the brake-cylinder and closing the exhaust-port,The followingpassages are now open: A pathway leads. from openingthrough pa'ssa'gei'i, valve '2, port 24, passage Q 8,'Valv e 3 toopening 11, thence to the brakecylinder. Another communication s, fromopening 3,0throughv ports 27 and 26' to open- 'ing ,11, thence tothellbrake-cylinder. Yet another airpathwayis from openingv 10 throughchamberB, opening 50, ports '15,

, piston-port l7, and port I23ut o .openingfll,

thence to thebrake-cylinder. The auxiliary reservoir and the train-pipebeing thus brought suddenly into communication with thebrfake-cylinderpassageswill cause checkyalve '20 tolbeLimmediately u'nsea'ted andtrain-pipe air will pass along said path between opening 0am openinglli,thence directly. into the brake-cylinder, Ithus effecting the quickinitial application of'Ythe brakes fu'ithe'r' reduction f Pressure inthe train-pipe that will'be sufi icient to accelerate th'eaction of thevalve fmecha nisinson .the cars follow'ing. The valve -lpiston part willin the meantime beheld to itsoutward position (toward the right) .bytherelatively higher air-pressurefroinfthe auxiliary reservoir, which isdelivered through large passage '30,whilethe'transmission oftheauxiliary-reservoir air from passage 3 0 ito the brake-cylinder isretarded by havingto pass through the restricted port 2%. JAfter'th'eair-pressures in the train-pipeand the brake ecylin'der have equalizedauxiliary-reservoir air will continue to flow from theauxiliaryreservoir into the brake-cylinder untilithere is anequalization of air-pressureinboth said ausiliaryireservoir andbrake-cylinder. Ilhen adj ustingstem 31, together with the train pipepressure, will I move the valve device toward the leftiuntil partition Ecovers port 24. It will be seen that tion by the auxiliaryueservoirpressure, the return movement beingproduced by the trainpipe pressure oradjusting stem 31, or both combined, as hereinbefore set forth; Itwillbe noted that by restricting the How of auxiliaryreservoirair aconsiderable volumeof train pipe airis allowedto flow freely intothebrakecylinder, notwithstanding the admission to theZbrake-cylinder atthe same time of a small volumeof the auxiliaryqeservoir air under ahigher pressure. An appreciable period of time is required to raiselthepressure in the brake-cylinder to thatin the auxiliary reservoir, anditzis during this intervaliand before the pressure inthebrake-cyh,inder'is raised to that inthe train-pipe that .the air in the latterisfree toenter the brakeeylinder. To release the brakes, a sufiicientamountofair is admitted from the train-reservoir K to the train-pipe toovercome the resistanceof the auxiliary-reservoir pressure and friction.of the valve'mechanism and move the valve device-tothe en d ofitsstroke,

(toward. the left, as shown ,in' '2, &c.,)

and thereb y establish "a co nmunication between the brake-cylinder andthe atmosphere by way of the exhaustpassage 25.v It will be noted.thatports'26and. 27 are brought into use. only'when fan emergency action ofthe Valve device takes place. In making a gradual stop the valve deviceis not movedi ar enough to the ii 7 to. communicate with eachother.

' In Fig. 8 I haveillu'strated an arrangement in whic htwo valve devices(such as shown in Fig. 2) are so coupled up that both parts X' and Yareper nanently and independently connected to the train-pipe, the;brake-cy1- the valve-piston part is movedin one direev 1 I00. ght toallow'ports'26 and 27 inder, and the auxiliary reservoir; but the valvedevices of each part X and Y control 7 the various port's attheappropriate'tim and IIO the action of one of said wvalve devices willalways be absolutely independent of the con- V dition or action oftheother valvedevice. In

other Words, the valves 2a'nd 3 (part X) being set t'oobstruct theair-passages 7 ,8,which said valves cohtroLandvalves 2' 3 (part Y)permitting the passage ways, which I they control, to

vice of, pa'rtY will act in tliemanner hereinbefore set forth,describingtheoperation'of asingle valve'device. 'In making either agradual stop: Oranemergency stop the engineers valve is manipulated in"exactly the same manner as when controlling the Westinghouse system, wrming thesame manner jinwhich my .present'single' valve device iscontrolled, In making the. gradual stop the,

valve device in part 1Y4 controls "the ,airfpr essureIn'ecessarytofmakethe}. stop and acts as previously set forth herein. In the' meantime thevalve device igpartg; win remain quiescent. for thereasonsralreadyi'setforthghereinl be open, then. the valvedevice of part X must 'act as adifferential valve device, as, pre

viously set forthhe'rein', while the valve d'e-" 12o \Vhen an emergencystop is to be made, air is discharged from the train-pipe, therebyreducing the pressure about twenty pounds. The preponderance ofair-pressu re will then be on the auxiliary-reservoir side of both ofsaid valve devices. Therefore they will immediately move toward theright to the ends of their paths. This will open five paths throughwhich the air-pressure will travel to reach the brake-cylinder. The saidpaths are as f 01- lows: The train pipe discharges into thebrake-cylinder th rough ports 15 in both valve devices, and thencethrough ports 23 to the brake-cylinder. Another path leads from openings30 (in both valve cases) through ports 27 and 26 (part X) to thebrake-cylinder, and a fifth path leads from opening 30 (part Y) throughpassage 7, valve 2, around to port 24, thence through valve 3 to thebrake-cylinder. To release the brakes, airis admitted as previouslydescribed, and the valve devices will move to their normal position tothe left, at which time the air confined in the brakecylinder escapesthrough one outlet onlyviz., through passage 8, valve 3', restrictedport 24, and exhaust-port 25. The partition E in part X is exposed tothe atmosphere through vent 1. It will be observed from the foregoingdescription that if one of the valve devices failed to perform its workthe other device would act promptly. This is because the train-pipepressure and the auxiliary-reservoir pressure act upon the pistons ofsaid valve devices simultaneously, independently,

and differentially. From the explanation herein set forth it will benoted that I may use one of said parts (X or Y) for gradual stops, whilethe other part may be used for quickaction or emergency stops only.Either part X or Y (when arranged as illustrated in Figs. 7 and 8) maybetransformed at will by means of handle 4 from a graduation valve deviceto an emergency valve device, and vice versa.

I do not limit my invention to any particular kind or shape of valve.

I am aware that it has been proposed to control the director emergencycommunication between the train-pipe and the brake-cylinder by means ofa supplemental valve and piston which is unconnected with the mainvalvepiston, but upon the movement of which said supplemental piston (toobtain motion) must depend for a supply of air-pressure, and suchconstruction, which involves an operation and arrangement different fromthat of my invention, I therefore hereby disclaim.

What I claim is-- 1. In an air-brake system, the combination of atrain-pipe having a direct communication a with two adjacent piston orvalve chambers,

a communication between an auxiliary reservoir and a brake-cylinder, acommunication between the train-pipe and the brake-cylinder, arestricted exhaust-passage between the brake-cylinder and theatmosphere, a valve device in one of said chambers and adapted tocontrol said exhaust and also admit airfrom the auxiliary reservoir tosaid brakecylinder when such valve device is in its normal condition,and a normally inert valve device in the remaining or second of saidchambers and adapted to admit air-pressure sufficient to apply thebrakes independently of the condition of the first -mentioned valvedevice in an emergency application, the said restricted exhaust beingadapted to restrict the'escape of air from the brake-cylinder if thefirst-mentioned valve device should fail to close the exhaust when anemergency-brake application is made.

2. In an air-brake system, the combination of a passage from thetrain-pipe, a passage from the brake-cylinder which is smaller or morerestricted than said train-pipe passage, and a valve device, consistingof a valve connected with a ported piston, coacting with both of saidpassages and controlling communicatioh between said train-pipe passageand the auxiliary reservoir and also between said brake-cylinder and theexhaust whereby when it is desired to release the brakes, the trainpipeair will have a passage through said ported piston and thence through alarge passage-way to the auxiliary reservoir, the brakecylinder air willhave a passage-way through a valve-controllod restricted passage to theatmosphere.

3. A valve apparatus for automatic airbrakes, having in combination twoports or passages communicating with the brake-cylinder, one of saidpassages being small and from the auxiliary reservoir and the other alarge passage from the train-pipe, so that the flow ofauxiliary-reservoir air is restricted as compared with the flow oftrain-pipe air when both are flowing to the brake-cylinder during anemergency brake action, a ported piston actuated in both directions byair-pressure, a stem having one end suit-ably connected with saidpiston, and a suitable valve operated by said stem to open and close thepassage from the auxiliary reservoir whilesaid piston controls thevalved passage from the train-pipe to the brake-cylinder and opens thesame for emergency stops only.

4. I11 an air-brake system, the combination of a passage from thetrain-pipe, a passage from the auxiliary reservoir which is smaller ormore restricted than said trainpipe passage, and a valve deviceconsisting of a valve which is mechanically connected to and moved inboth directions by a ported piston, the said valve device coacttng withboth of said passages and controlling communication between them and thebrake-cylinder whereby, when an emergency application I of the brakes isdesired the train-pipe air and the auxiliary-reservoir air, the formerat a lower pressure than the latter, will both have passages open to thebrake-cylinder as follows: said train-pipe air-passage being throughsaid piston and thence through a by-path in the valve-case, the saidauxiliary-reservoir air-passage being through another pathin thevalve-case and controlled by said valve.

5. A valve mechanism for automatic airbrakes having in combination,apass'age leading to the brake-cylinder from the train-pipe, a passageleading to the brake-cylinder from the auxiliary-reservoir, which issmaller or more restricted than said train-pipe passage,

.a ported piston actuated in one direction, by

pressure from the train-pipe to close said trainpipe passage, andactuated in the opposite direction by pressure from the auxiliaryreservoir to open said train-pipe passage, a stem having one endsuitably connected with said piston, and a valve suitably connected withsaid stem and moved thereby to controlsaid passage between the auxiliaryreservoir and the brake-cylinder, while said piston controls the passagebetweensaid train-pipe and the brake-cylinder and opens said passage foremergency stops only. 7

6. In an automatic air-brake system, the combination, with thetrain-pipe, an auxiliary reservoir, and a valve device, of a secondvalve device which is adapted to act absolutely independent of theaction or inaction of the first-mentioned valve device and only whenemergency brake applications are made, both of said valve devices beingadapted to admit air 'from the auxiliary reservoir to brake-cylinder,and a passage from said trainpipe to said brake-cylinder, and controlledby said second valve device.

7. In an air-brake system, the combination of a train-pipe, two valvedevices communieating therewith, the piston parts of both of saiddevices being constantly under the trainpipe air-pressure and each ofsaid devices being adapted to operate absolutely independent of eitherthe action or inaction of -the other and each of such devices beingadapted tocontrol a passage leading from the auxiliary reservoir to thebrake-cylinder.

S. In an air-brake mechanism, the combinaticn of a train-pipe having aconnection to a valve-device chamber or casing, a communication betweensaid chamber or casing and an auxiliary reservoir, a comm unicationbetween said chamber or casing and a brake-cylinder, and a normallyinert differential piston-valve device located within said chamber orcasing and adapted to act when making emergency stops only, andestablish a check-valved communication between said train-pipe andsaidbrake-cylinder, the piston of said valve device being actuated byauxiliary-reservoir air-pressure in one direction to open or establishthe latter communication, and moved by train-pipe air-pressure to cutoffor close said communication, during such movements said device operatingfree from any other valve dovice.

9. .In an air-brake system, the combination of a train-pipe,an auxiliaryreservoir, a brakecylinder, two valve devices adapted to act absolutelyindependent of each other, air

communication between said train-pipe and the auxiliary reservoir, aircommunication between said. train-pipe and said brake-cylinder, aircommunication between said aux iliary reservoir and said brake-cylinderand .a restricted air-passage between said brakecylinder and theatmosphere, each of said valve devices being adapted to infi uence theair movement from said auxiliaryreservoir to said brake-cylinder, one ofsaid'valve devices operating only during emergency applications of thebrakes.

10. In an air-brakesystelmthe combination of a valve device,substantially'as described, having a ported piston mechanicallyconnected with a valve, a chamber or case for-said piston, a chamber forsaid valve, a passage from the train-pipe to said piston-chamber, a

passage from said piston-chamber to the auxiliary reservoir, a passagefrom said piston-' chamber to the brake-cylinder, arestricted passagefrom said auxiliary reservoir tov the brake-cylinder, and a restrictedpassage from said brake-cylinder to the exhaust-opening, the said pistonwhen at oneend of its cylininder forms a part of a communication between said train-pipe and said auxiliary reservoir, said Valve in themeantime forming a part of a communication between said brakecylinderand said exhaust-openin g, but when said piston is at the other end ofits cylinder it becomes a part of a communication between saidtrain-pipe and said brake-cylinder, said communication being open foremergency stops only, and said valve, in themeantiine, opening acommunication between the auxiliary reservoir and said brake-cylinder.

11. In an air-brake mechanism, the com'bination of a train-pipe having atubular connection to two adjacent valve-device chambe'rs or casings, atubularconnection from each of said chambers or casings to'abrakecylinder, a tubular connection fromeach of said chambers or casingsto an auxiliary reservoir, a passage from the brakecylinder to theatmosphere, a graduating-valve device located within one of saidchambers orcasings, and a normally inert diderential piston- -valvedevice located within the other chamber or casing, the latterVaIVG'dGVlCQ being ,adapted to operate when making emergency stops only,and control the communication between said train-pipe and saidbrake-cylinder, each piston of said valve devices be" ing actuated byauxiliary-reservoir air-pressure in one direction to open or establishsaid communications and moved by train-pipe airpressure in the oppositedirection to close or cut off said communications, in operationsaidlvalve devices acting absolutelyindependent of each other.

Signed at New York, in the county of New York and State of New York,this 17th day of January, A. D. 1898. v Y

' GRANVILLE. T. WOODS. Witnesses: l 4

E. RILEY, ORY CANE.

